Dual layer sandwich for thermal management

ABSTRACT

A thermal protection system including a plurality of layers. A first layer includes a passive insulation material. A second layer includes a phase change insulation material. A third layer is positioned between the first layer and the second layer to separate the passive insulation material from the phase change insulation material. A structural system extends through the first layer, the second layer, the third layer, or a combination thereof.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationhaving Ser. No. 14/462,175, filed on Aug. 18, 2014, which isincorporated herein in its entirety.

TECHNICAL FIELD

The present teachings relate to the field of thermal protection systems(“TPS”) and, more particularly, to thermal protection systems used onhypersonic vehicles such as missiles, aircraft, spacecraft, and thelike.

BACKGROUND

Vehicles travelling at hypersonic velocities may be exposed to hightemperatures due to friction generated by contact with the passing fluid(e.g., air). For example, the nose and the leading edges of the wings ofa spacecraft may be exposed high temperatures during re-entry into theatmosphere. To prevent these high temperatures from adversely affectingthe vehicle, a thermal protection system is coupled to the outer surfaceor “skin” of the vehicle to insulate the vehicle.

The thermal protection system may include a plate made of a bondedceramic insulating foam tile, ceramic, or a metallic standoff panel withan insulating blanket. The plate may be bonded or fastened to the skinof the vehicle. While the plate may insulate the vehicle from the heat,the weight of the plate may make the plate a very heavy addition for thevehicle to carry. As will be appreciated, it is desirable to keep theweight of airborne vehicles to a minimum. In addition to addingundesirable weight, the plate may have a thickness from about 2 cm toabout 10 cm. As the thickness of the plate increases, the internalvolume for other components decreases. Therefore, an improved thermalprotection system for a hypersonic vehicle would be desirable.

SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects of the present teachings. This summary isnot an extensive overview, nor is it intended to identify key orcritical elements of the present teachings, nor to delineate the scopeof the disclosure. Rather, its primary purpose is merely to present oneor more concepts in simplified form as a prelude to the detaileddescription presented later.

A thermal protection system including a plurality of layers isdisclosed. A first layer includes a passive insulation material. Asecond layer includes a phase change insulation material. A third layeris positioned between the first layer and the second layer to separatethe passive insulation material from the phase change insulationmaterial. A structural system extends through the first layer, thesecond layer, the third layer, or a combination thereof.

In another embodiment, the thermal protection system includes a firstlayer including a first ceramic matrix composite material. A secondlayer is coupled to the first layer, and the second layer includes apassive insulation material. A third layer is coupled to the secondlayer such that the second layer is positioned between the first andthird layers. The third layer includes a second ceramic matrix compositematerial. A fourth layer is coupled to the third layer such that thethird layer is positioned between the second and fourth layers. Thefourth layer includes a phase change insulation material. A fifth layeris coupled to the fourth layer such that the fourth layer is positionedbetween the third and fifth layers. The fifth layer includes a thirdceramic matrix composite material, a carbon reinforced plastic material,a carbon fiber reinforced plastic material, a polymer matrix compositematerial, or a combination thereof. A structural system may includefirst and second truss pins. The first truss pin may be coupled to thefirst layer and coupled to the third layer. The second truss pin may becoupled to the third layer and coupled to the fifth layer.

A vehicle including a thermal protection system is also disclosed. Thevehicle includes a body and the thermal protection integrated with thebody. The thermal protection system includes a first layer including afirst ceramic matrix composite material. A second layer is coupled tothe first layer, and the second layer includes a passive insulationmaterial. A third layer is coupled to the second layer such that thesecond layer is positioned between the first and third layers. The thirdlayer includes a second ceramic matrix composite material. A fourthlayer is coupled to the third layer such that the third layer ispositioned between the second and fourth layers. The fourth layerincludes a phase change insulation material. A fifth layer is coupled tothe fourth layer such that the fourth layer is positioned between thethird and fifth layers. The fifth layer includes a third ceramic matrixcomposite material, a carbon reinforced plastic material, or acombination thereof. A structural system extends through the secondlayer, the third layer, the fourth layer, or a combination thereof.

The features, functions, and advantages that have been discussed can beachieved independently in various implementations or may be combined inyet other implementations further details of which can be seen withreference to the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate the present teachings andtogether with the description, serve to explain the principles of thedisclosure. In the figures:

FIG. 1 is a top view of a vehicle having an illustrative thermalprotection system.

FIG. 2 is a cross-sectional view of the vehicle taken along line 2-2 inFIG. 1.

FIG. 3 is a cross-section of a perspective view of the thermalprotection system shown in FIG. 1.

FIG. 4 is an enlarged cross-sectional view of a portion of the thermalprotection system shown in FIG. 3.

FIG. 5 is another enlarged cross-sectional view of a portion of thethermal protection system shown in FIG. 3.

It should be noted that some details of the Figures have been simplifiedand are drawn to facilitate understanding of the present teachingsrather than to maintain strict structural accuracy, detail, and scale.

DETAILED DESCRIPTION

Reference will now be made in detail to examples of the presentteachings which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts.

FIG. 1 is a top view of a vehicle 100 having an illustrative thermalprotection system 200. As shown, the vehicle 100 is a space shuttle.However, as will be appreciated, the vehicle 100 may be any vehicle thatmay be exposed to elevated temperatures (e.g., greater than about 260°C.). In at least one embodiment, the vehicle 100 may be a missile, arocket, a spacecraft, etc. that may be exposed to elevated temperatureswhen travelling at supersonic speeds, hypersonic speeds, or greaterspeeds. In other embodiments, the vehicle 100 may be, for example, anairplane that is exposed to elevated temperatures proximate to a heatsource such as an engine or exhaust port 108.

FIG. 2 is a cross-sectional view of the vehicle 100 taken along line 2-2in FIG. 1. Referring to FIGS. 1 and 2, the vehicle 100 includes a body102 that defines an inner volume 110. In at least one embodiment, thethermal protection system 200 is coupled to the body 102. However, asshown in FIG. 2, in another embodiment, the thermal protection system200 is structurally integrated with the body 102 to avoid bonding orcoupling the thermal protection system 200 to the body 102. This may bereferred to as a structurally-integrated thermal protection system(“SITPS”). In this way, the thermal protection system 200 does notsignificantly increase the weight and/or decrease the volume 110 of thebody 102. For example, the thermal protection system 200 may be a partof the body 102, and the first layer 210 (introduced below) of thethermal protection system 200 may serve as a portion of the outersurface or “skin” of the body 102.

The thermal protection system 200 may be positioned proximate to anyportion of the body 102 that may be exposed to elevated temperatures. Assuch, the thermal protection system 200 may cover all or a portion ofthe body 102. For example, the thermal protection system 200 may bepositioned proximate to the nose 104, the leading edges of the wings106, the engine and/or exhaust ports 108, the landing gear door (notshown), a combination thereof, or the like.

FIG. 3 is a cross-section of a perspective view of the thermalprotection system 200 shown in FIG. 1, and FIG. 4 is an enlargedcross-sectional view of a portion of the thermal protection system 200shown in FIG. 3. The thermal protection system 200 is in the form of asandwich structure including a plurality of layers (five are shown: 210,220, 230, 240, 250). Although five layers 210, 220, 230, 240, 250 areshown, it will be appreciated that more or fewer layers may be usedwithout departing from the scope of the disclosure.

The first or “outer” layer 210 may be referred to as an outboardfacesheet layer. The outboard facesheet layer 210 has a thickness fromabout 0.5 mm to about 5 mm, about 1 mm to about 4 mm, or about 2 mm toabout 3 mm. The outboard facesheet layer 210 is made of ceramic matrixcomposite (“CMC”) materials 212.

The CMC materials 212 may be oxide-based and include truss, fluted-core,honeycomb, or other sandwich constructions including fiberreinforcements. The fiber reinforcements may include alumina (e.g.,NEXTEL® 610), alumina mullite (e.g., NEXTEL® 720), aluminoborosilicate(e.g., NEXTEL® 312 or 440), quartz, glass, or a combination thereof(NEXTEL is a registered trademark of Minnesota Mining and ManufacturingCompany of St. Paul, Minn.). The oxide-based CMC materials 212 may alsoinclude matrices that include alumina, aluminosilicate, alumina mullite,mullite glass, or a combination thereof.

The CMC materials 212 may also be non-oxide-based and include truss,fluted-core, honeycomb, or other sandwich constructions including fiberreinforcements. These fiber reinforcements may include carbon, siliconcarbide, silicon nitride, silicon boride, silicon boronitride, or acombination thereof. The non-oxide-based CMC materials 212 may alsoinclude matrices that include carbon, silicon carbide, silicon nitride,silicon boride, hafnium carbide, zirconium carbide, other nitrides orcarbides, or a combination thereof.

The second layer 220 is coupled to and positioned inward from theoutboard facesheet layer 210. The second layer 220 is a sandwich layerthat may serve as a passive insulation layer and is referred to as suchgoing forward. The passive insulation layer 220 includes a passiveinsulation material 222. The passive insulation material 222 has athickness from about 5 mm to about 50 mm, about 10 mm to about 40 mm, orabout 15 mm to about 30 mm.

The passive insulation material 222 may be rigid or flexible. Moreparticularly, the passive insulation material 222 may be a tile, abatting, a foam, or a combination thereof. The passive insulationmaterial 222 may include ceramic fibers or batting including alumina,silica, or a combination thereof. The passive insulation material 222may also include ceramic tile insulation. The ceramic tile insulationmay be or include ceramic tile including alumina and silica fibers,alumina enhanced thermal barrier (“AETB”), or a combination thereof.

The third layer 230 is coupled to and positioned inward from the passiveinsulation layer 220. The third layer 230 may be referred to as a septumlayer. The septum layer 230 has a thickness from about 0.1 mm to about 5mm, about 0.25 mm to about 3 mm, or about 0.5 mm to about 2 mm.

The septum layer 230 may include any one or more of the materials listedabove with respect to the outboard facesheet layer 210. The septum layer230 may be made from the same materials as the outboard facesheet layer210 or different materials.

The septum layer 230 may serve to separate the passive insulation layer220 from the phase change insulation layer 240 (introduced below). Moreparticularly, the septum layer 230 may be a non-porous layer thatprevents the phase change insulation material 242 from entering orcontacting the passive insulation material 222. This may allow thethermal protection system 200 to have a plurality of insulation layers(e.g., layers 220, 240). In at least one embodiment, the thickness ofthe septum layer 230 may be less than or equal to about 25% of thethickness of the passive insulation layer 220 and less than or equal toabout 25% of the thickness of the phase change insulation layer 240.

The fourth layer 240 is coupled to and positioned inward from the septumlayer 230. The fourth layer 240 is a sandwich layer similar to layer220, but made of a different insulation material. For example, thefourth layer 240 includes a phase change insulation material 242 and isreferred to as a phase change insulation layer going forward. The phasechange insulation material 242 has a thickness from about 2 mm to about25 mm, about 4 mm to about 20 mm, or about 6 mm to about 15 mm.

The phase change insulation layer 240 includes a carrier 244 (e.g., aceramic foam carrier) having the phase change material 242 positionedtherein. The carrier 244 may include silicon carbide, carbon, alumina,silica, or a combination thereof. The phase change material 242 mayinclude melamine, lithium fluoride, germanium nitride, germanium oxide,gallium nitride, or a combination thereof.

The phase change material 242 may be in a solid phase when the thermalprotection system 200 is exposed to a temperature that is less than orequal to a predetermined temperature. The predetermined temperature maybe below the selected phase change material's temperature ofdecomposition. For example, the predetermined temperature may be fromabout 100° C. to about 300° C., about 300° C. to about 700° C., or about700° C. to about 1400° C. However, as will be appreciated, thepredetermined temperature may depend, at least partially, on the type ofthe phase change material 242, the composition of the phase changematerial 242, the duration of exposure to the temperature, or acombination thereof.

A lower predetermined temperature may keep the body 102 and/or interiorvolume 110 of the vehicle 100 cooler. However, the lower predeterminedtemperature may also maintain the outboard side of the phase changematerial 242 at a relatively low temperature, thereby reducing theamount of heat that is radiated outward from the body 102 of the vehicle100. Radiation is one of the ways that heat is transferred from the body102 of the vehicle 100. As such, the thermal protection system 200 mayinclude the passive insulation material 222 on the outside to facilitateradiation and the phase change insulation material 242 on the inside tomaintain the body 102 at a lower temperature.

When the phase change material 242 reaches or exceeds the predeterminedtemperature, the phase change material 242 may transform from the solidphase to a liquid phase. The phase change material 242 may remainencapsulated within the carrier 244 in both the solid and liquid phases.The heat energy may be converted and dissipated as the material 242transforms from the solid phase to the liquid phase. This process mayalter (e.g., slow) the rate of heat transfer from a hot exterior regionto a cool interior region. Once the phase change material 242 fallsbelow the predetermined temperature, the phase change material 242transforms back into the solid phase.

The phase change material 242 may vaporize when exposed to a second,higher predetermined temperature. As with the first predeterminedtemperature, the second predetermined temperature may also depend atleast partially, on the type of the phase change material 242, thecomposition of the phase change material 242, the duration of exposureto the temperature, or a combination thereof. The phase change material242 may decompose after vaporizing. In at least one embodiment, the heatcapacity including decomposition for a 1.3 cm thick phase changeinsulation layer 240 may range from about 2 kJ/cm² to about 35 kJ/cm² ormore, depending on the type of phase change material 242.

The fifth layer 250 is coupled to the phase change insulation layer 240.The fifth layer 250 may be referred to as an inboard facesheet layer.The inboard facesheet layer 250 may serve as an inner surface of thebody 102 of the vehicle 100. The inboard facesheet layer 250 has athickness from about 0.5 mm to about 5 mm, about 1 mm to about 4 mm, orabout 2 mm to about 3 mm. The outboard facesheet layer 210, the inboardfacesheet layer 250, or both may be rigid to maintain the structure ofthe thermal protection system 200.

The inboard facesheet layer 250 may include any one or more of thematerials listed above with respect to the outboard facesheet layer 210.For example, the inboard facesheet layer 250 may be made from the samematerials as the outboard facesheet layer 210. In another example, theinboard facesheet layer 250 is made from different materials than theoutboard facesheet layer 210.

The inboard facesheet materials 252 may also include carbon reinforcedplastic (“CRP”), carbon fiber reinforced plastic (“CFRP”), or polymermatrix composite (“PMC”). The CFRP materials may include carbon,graphite, glass, aramid, or a combination thereof. The CRP and/or CFRPmay also be or include matrices and/or resins including bismaleimide(“BMI”), epoxy, polyimide (“PI”), polyetheretherketone (“PEEK”), cyanateester (“CE”), or a combination thereof.

As shown in FIG. 4, the thermal protection system 100 includes astructural system 260, such as a plurality of truss pins 262, forstructural support. The truss pins 262 are coupled to the outboard andinboard facesheet layers 210, 250. More particularly, ends of the trusspins 262 are embedded in the outboard and inboard facesheet layers 210,250. The truss pins 262 may extend through the passive insulation layer220, the septum layer 230, and the phase change insulation layer 240(including the carrier 244). The passive insulation material 222 and thephase change insulation material 242 may surround the truss pins 262.

The truss pins 262 may be optional when the passive insulation material222 and/or the carrier 244 are structural. For example, instead of, orin addition to, the truss pins 262, the structural system 260 mayinclude flutes, baffles, honeycombs, a combination thereof, or the likefor structural support.

FIG. 5 is another enlarged cross-sectional view of the structural system260 shown in FIG. 3 showing a first plurality of truss pins 262-1coupled to the outboard facesheet layer 210 and the septum layer 230 anda second plurality of truss pins 262-2 coupled to the septum layer 230and the inboard facesheet layer 250. As used with respect to the trusspins, “coupled to” refers to the pins being embedded in, extendingthrough, being attached directly to a surface of, or being attachedindirectly to a surface of a layer. The truss pins 262-1 include a body264 and opposing ends 266, 268. The bodies 264 of the truss pins 262-1extend through the passive insulation layer 220. As such, the passiveinsulation material 222 may surround the bodies 264 of the truss pins262-1.

As shown, the ends 266, 268 are curved, bent, and/or angled with respectto the body 264. For example, the ends 266, 268 may be oriented at anangle 270 with respect to the body 264. The angle 270 may be from about45° to about 75°, about 75° to about 105°, about 105° to about 135°, orabout 45° to about 135°. The ends 266, 268 of the truss pins 262-1 maybe substantially parallel to the outboard facesheet layer 210, theseptum layer 230, or both. As such, the body 264 may be oriented at theangle 270 with respect to the outboard facesheet layer 210, the septumlayer 230, or both.

The truss pins 262-1 are coupled to the outboard facesheet layer 210. Asshown, the first ends 266 may be embedded in the outboard facesheetlayer 210. In another embodiment, the truss pins 262-1 may extendthrough the outboard facesheet layer 210 such that the first ends 266are positioned on the opposite side of the outboard facesheet layer 210from the bodies 264. In this embodiment, the bent first ends 266 maysecure the truss pins 262-1 to the outboard facesheet layer 210. In yetanother embodiment, the first ends 266 may be secured to the outboardfacesheet layer 210 with an adhesive.

The truss pins 262-1 are also coupled to the septum layer 230. As shown,the second ends 268 may be embedded in the septum layer 230. In anotherembodiment, the truss pins 262-1 may extend through the septum layer 230such that the second ends 268 are positioned on the opposite side of theseptum layer 230 from the bodies 264. In this embodiment, the bentsecond ends 268 may secure the truss pins 262-1 to the septum layer 230.In yet another embodiment, the second ends 268 may be secured to theseptum layer 230 with an adhesive.

Similarly, the truss pins 262-2 include a body 274 and opposing ends276, 278. The bodies 274 of the truss pins 262-2 extend through thephase change insulation layer 240 (including the carrier 244). As such,the phase change insulation material 242 may surround the bodies 274 ofthe truss pins 262-2.

As shown, the ends 276, 278 are curved, bent, and/or angled with respectto the body 274. For example, the ends 276, 278 may be oriented at anangle 280 with respect to the body 274. The angle 280 may be from about45° to about 75°, about 75° to about 105°, about 105° to about 135°, orabout 45° to about 135°. The angle 280 may be the same as or differentthan the angle 270. The ends 276, 278 of the truss pins 262-2 may besubstantially parallel to the septum layer 230, the inboard facesheetlayer 250, or both. As such, the body 274 may be oriented at the angle280 with respect to the septum layer 230, the inboard facesheet layer250, or both.

The truss pins 262-2 are coupled to the septum layer 230. As shown, thefirst ends 276 may be embedded in the septum layer 230. In anotherembodiment, the truss pins 262-2 may extend through the septum layer 230such that the first ends 276 are positioned on the opposite side of theseptum layer 230 from the bodies 274. In this embodiment, the bent firstends 276 may secure the truss pins 262-2 to the septum layer 230. In yetanother embodiment, the first ends 276 may be secured to the septumlayer 230 with an adhesive.

The truss pins 262-2 are also coupled to the inboard facesheet layer250. As shown, the second ends 278 may be embedded in the inboardfacesheet layer 250. In another embodiment, the truss pins 262-2 mayextend through the inboard facesheet layer 250 such that the second ends278 are positioned on the opposite side of the inboard facesheet layer250 from the bodies 274. In this embodiment, the bent second ends 278may secure the truss pins 262-2 to the inboard facesheet layer 250. Inyet another embodiment, the second ends 278 may be secured to theinboard facesheet layer 250 with an adhesive.

Referring to FIGS. 2-5, the thermal protection system 200 may behave asa single layer. For example, the outboard and inboard facesheet layers210, 250 may be in tension and compression as if there is only oneinsulation layer in the system, even though there are two (or more)insulation layers 220, 240. The septum layer 230 does not affect thestructure of the insulation layers 220, 240, but the septum layer 230may prevent the structural system 260 from buckling during expansion andcontraction of the insulation layers 220, 240.

With high thermal loading, the outboard facesheet layer 210 and thepassive insulation layer 220 may approach the temperature of theexterior environment, thus reducing the rate of heat transfer. Thepassive insulation layer 220 may absorb a portion of the heat, and thephase change insulation layer 240 may dissipate an additional portion ofthe heat as the phase change insulation layer 240 changes phases (e.g.,melts or evaporates).

The thermal protection system 200 disclosed herein may providesubstantially equivalent heat protection as a conventional systemincluding a passive insulation layer (but no phase changing insulationlayer) while occupying less thickness, weight per unit area, and/orvolume. Similarly, the thermal protection system 200 disclosed hereinmay provide substantially equivalent heat protection as a differentconventional system including a phase changing insulation layer (but nopassive insulation layer) while occupying less thickness, weight perunit area, and/or volume.

The thermal protection system 200 disclosed herein may be more durable(e.g., “all weather”) compared to conventional parasitic blankets andtiles. In addition, the thermal protection system 200 may be lowerweight and have a lesser thickness than parasitic standoff panels,blankets, or single layer thermal protection systems. As hypersonicvehicles 100 tend to be highly volume-constrained, a thermal protectionsystem 200 having equivalent heat protection with a lesser thicknesscompared to the conventional systems mentioned above may improve theperformance of the vehicle 100. This lesser thickness with equivalentheat protection may be achieved, at least partially, by the addition ofthe phase change insulation layer 240 as part of the sandwich structure.The thermal protection system 200 may also provide packaging andintegration benefits in applications such as landing gear doors, wherethe added stiffness of the thermal protection system 200 sandwichstructure may minimize sealing and flutter issues (compared to aparasitic thermal protection system over a thin structural door panel).

Although two insulation layers 220, 240 are shown and described, it willbe appreciated that other embodiments may use three or more insulationlayers. Although the insulation layers 220, 240 are described above asbeing made of a passive insulation material 222, and a phase changinginsulation material 242, respectively, it will be appreciated that theseare merely illustrative embodiments. For example, the layers 220, 240may both be made of a passive insulation material 222. In anotherexample, the layers 220, 240 may both be made of a phase changeinsulation material 242. In yet another example, the layer 220 may bemade of a phase change insulation material 242, and the layer 240 may bemade of a passive insulation material 222. Although passive insulationmaterials 222 and phase change insulation materials 242 are disclosed,other insulation materials are also contemplated herein.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the present teachings are approximations, thenumerical values set forth in the specific examples are reported asprecisely as possible. Any numerical value, however, inherently containscertain errors necessarily resulting from the standard deviation foundin their respective testing measurements. Moreover, all ranges disclosedherein are to be understood to encompass any and all sub-ranges subsumedtherein. For example, a range of “less than 10” can include any and allsub-ranges between (and including) the minimum value of zero and themaximum value of 10, that is, any and all sub-ranges having a minimumvalue of equal to or greater than zero and a maximum value of equal toor less than 10, e.g., 1 to 5. In certain cases, the numerical values asstated for the parameter can take on negative values. In this case, theexample value of range stated as “less than 10” can assume negativevalues, e.g. −1, −2, −3, −10, −20, −30, etc.

While the present teachings have been illustrated with respect to one ormore implementations, alterations and/or modifications can be made tothe illustrated examples without departing from the spirit and scope ofthe appended claims. It will be appreciated that structural componentsand/or processing stages can be added or existing structural componentsand/or processing stages can be removed or modified. Furthermore, to theextent that the terms “including,” “includes,” “having,” “has,” “with,”or variants thereof are used in either the detailed description and theclaims, such terms are intended to be inclusive in a manner similar tothe term “comprising.” The term “at least one of” is used to mean one ormore of the listed items can be selected. Further, in the discussion andclaims herein, the term “on” used with respect to two materials, one“on” the other, means at least some contact between the materials, while“over” means the materials are in proximity, but possibly with one ormore additional intervening materials such that contact is possible butnot required. Neither “on” nor “over” implies any directionality as usedherein. The term “about” indicates that the value listed may be somewhataltered, as long as the alteration does not result in nonconformance ofthe process or structure to the present teachings. Finally, “exemplary”indicates the description is used as an example, rather than implyingthat it is an ideal. The present disclosure provides specificimplementations without being exhaustive, and other implementations ofthe present teachings may be apparent to those skilled in the art fromconsideration of the specification and practice of the disclosureherein. It is intended that the specification and examples be consideredas exemplary only, with a true scope and spirit of the present teachingsbeing indicated by the following claims.

1. A thermal protection system, the system comprising: a first layercomprising a passive insulation material; a second layer comprising aphase change insulation material; a third layer positioned between thefirst layer and the second layer to separate the passive insulationmaterial from the phase change insulation material; and a structuralsystem that extends through the first layer, the second layer, or acombination thereof.
 2. The thermal protection system of claim 1,wherein the structural system comprises one or more truss pins, flutes,baffles, honeycombs, or a combination thereof.
 3. The thermal protectionsystem of claim 1, wherein the structural system comprises a truss pinthat extends through the first layer, the second layer, and the thirdlayer.
 4. The thermal protection system of claim 1, wherein thestructural system comprises a truss pin that is coupled to the thirdlayer.
 5. The thermal protection system of claim 4, wherein an end ofthe truss pin is embedded in the third layer.
 6. The thermal protectionsystem of claim 4, wherein an end of the truss pin is oriented at anangle with respect to a body of the truss pin, and wherein the angle isfrom about 45° to about 135°.
 7. The thermal protection system of claim6, wherein the end of the truss pin is on an opposite side of the thirdlayer from the body.
 8. The thermal protection system of claim 6,wherein the end of the truss pin is substantially parallel with thethird layer.
 9. A thermal protection system, the system comprising: afirst layer comprising a first ceramic matrix composite material; asecond layer coupled to the first layer, the second layer comprising apassive insulation material; a third layer coupled to the second layersuch that the second layer is positioned between the first and thirdlayers, the third layer comprising a second ceramic matrix compositematerial; a fourth layer coupled to the third layer such that the thirdlayer is positioned between the second and fourth layers, the fourthlayer comprising a phase change insulation material; a fifth layercoupled to the fourth layer such that the fourth layer is positionedbetween the third and fifth layers, the fifth layer comprising a thirdceramic matrix composite material, a carbon reinforced plastic material,a carbon fiber reinforced plastic material, a polymer matrix compositematerial, or a combination thereof; and a structural system comprising:a first truss pin coupled to the first layer and the third layer; and asecond truss pin coupled to the third layer and the fifth layer.
 10. Thethermal protection system of claim 9, wherein a first end of the firsttruss pin is embedded in the first layer.
 11. The thermal protectionsystem of claim 10, wherein a second end of the first truss pin isembedded in the third layer.
 12. The thermal protection system of claim9, wherein the first truss pin extends through the first layer such thatan end of the first truss pin is positioned on an opposite side of thefirst layer from a body of the first truss pin.
 13. The thermalprotection system of claim 12, wherein the end of the first truss pin isoriented at an angle with respect to the body of the first truss pin,and wherein the angle is from about 45° to about 135°.
 14. The thermalprotection system of claim 13, wherein the end of the first truss pin issubstantially parallel with the first layer.
 15. The thermal protectionsystem of claim 9, wherein the first truss pin extends through thesecond layer, and wherein the second truss pin extends through thefourth layer.
 16. A vehicle comprising: a body; and a thermal protectionintegrated with the body, the thermal protection system comprising: afirst layer comprising a first ceramic matrix composite material; asecond layer coupled to the first layer, the second layer comprising apassive insulation material; a third layer coupled to the second layersuch that the second layer is positioned between the first and thirdlayers, the third layer comprising a second ceramic matrix compositematerial; a fourth layer coupled to the third layer such that the thirdlayer is positioned between the second and fourth layers, the fourthlayer comprising a phase change insulation material; a fifth layercoupled to the fourth layer such that the fourth layer is positionedbetween the third layer and the fifth layer, the fifth layer comprisinga third ceramic matrix composite material, a carbon reinforced plasticmaterial, or a combination thereof; and a structural system that extendsthrough the second layer, the third layer, the fourth layer, or acombination thereof.
 17. The vehicle of claim 16, wherein the structuralsystem comprises: a first truss pin coupled to the first layer andcoupled to the third layer; and a second truss pin coupled to the thirdlayer and coupled to the fifth layer.
 18. The vehicle of claim 17,wherein a first end of the first truss pin is embedded in the firstlayer.
 19. The vehicle of claim 17, wherein the first truss pin extendsthrough the first layer such that an end of the first truss pin ispositioned on an opposite side of the first layer from a body of thefirst truss pin.
 20. The vehicle of claim 19, wherein the end of thefirst truss pin is substantially parallel with the first layer.